1. Technical Field
The present invention relates to pen-based computer systems. In particular, it relates to a method and apparatus for detecting pen strokes written on a paper form by an individual and automatically determining the correct form by analyzing the pen strokes of a writer.
2. Background Art
There are many procedures for which the first step is an individual filling out a paper form. In most situations, the data written on the form will ultimately be input to a computer system. Historically, this has required a labor intensive two-step procedure in which a first individual fills out a form, and then a second individual enters that data into a computer database.
The development of compact high-performance computers has resulted in many new applications which heretofore were not feasible due to their demand on system resources. One such application is the pen-based, or tablet, computer. Pen-based computer applications are particularly useful in mobile environments, especially where form data is used. For example, businesses such as delivery services which previously used paper forms can now use a pen-based tablet computer to hold a paper form, and to electronically capture the data as the user fills out the form. In this type of application, the system would normally keep a copy of the form image separate from the data input by the user. This allows the input data to be more conveniently stored and/or transmitted. The development of pen-based computers has allowed data written on a form to be directly stored in a computer rather than having to take a second step to transfer the data originally written on a paper form into a computer. However, pen captured data still requires optical character recognition (OCR) software to convert the pen stroke data captured by the pen-based computer to usable data.
The next step was the development of multi-page electronic documents. This type of document may, for example, be a patient questionnaire used by physicians to obtain basic health data from a patient, or any other application which requires multiple page forms. However, as the size of a multiple page document increases, determining which page within a document an individual is currently completing becomes more difficult. One difficulty associated with multiple page documents on tablet computers is caused by the need to identify which page in a multi-page electronic form is being filled out by an individual. It would be desirable to have a method of automatically identifying the form and individual pages so that data input by an individual could be automatically associated with the correct page of the correct form.
Another disadvantage to the prior art is that it requires explicit manual steps to initialize the data-gathering phase. For example, if a multi-part form is being used, the form must first be carefully aligned on the tablet or a registration procedure must be executed to instruct the tablet computer regarding the exact form placement. Then the specific form must be identified to the computer system. Once the form is identified, the current page must be identified whenever the user moves from one page to another in a multi-page form. As can be seen, this is a labor intensive process which is prone to error.
Unfortunately, these operations are clearly unsuitable for untrained users for the following reasons. First, there is little control over how carefully the person aligns the form. Second, we cannot ensure that an individual is taught how to identify forms or ensure that the form identification has taken place. Finally, it is not possible to ensure that an individual can be taught how to select pages or ensure that the person correctly re-selects the correct page every time they skip backwards or forwards within a multi-page form. As a result, even though electronic entry of data from forms has been developed, the process of electronically entering data written on forms has numerous disadvantages.
While addressing the basic desirability of using electronic, rather than paper forms, the prior art has failed to provide a multi-page electronic forms system which is capable of automatically identifying a form without an individual actively taking some step or steps to identify it.